/Engine/Source/Runtime/Experimental/Iris/Core/Public/Iris/DataStream/DataStream.h
Base struct for data stream records which are returned with WriteData calls and provided to ProcessPacketDeliveryStatus calls. It's up to each DataStream implementation to inherit, if needed, and store relevant information regarding what was written in the packet so that when ProcessPacketDeliveryStatus is called the DataStream can act on it appropriately depending on whether the packet was delivered or lost. The DataStream is responsible both for allocating and freeing its own records.
struct FDataStreamRecord